1. Field of the Invention
The present invention relates to a lens apparatus which has a mechanism for adjusting a lens unit, and to a camera which has the lens apparatus.
2. Description of Related Art
It is conventionally known that, since manufacture errors occur in individual components of lenses and barrels in a lens apparatus, favorable optical performance is achieved by performing a tracking adjustment of moving lenses in an optical axis direction, an inclination adjustment of lenses, and a decentering adjustment of decentering lenses.
Especially for a zoom lens apparatus, a number of components are used to form the lens apparatus and the manufacture errors in the respective components are accumulated to cause a large error in the whole lens apparatus. Among other things, in a collapsible zoom lens apparatus having a plurality of retractable barrels which can be moved in the optical axis direction and put into a camera body, the accumulation of the manufacture errors of the respective components is increased, so that an optical adjustment mechanism needs to be provided in order to achieve excellent optical performance.
To meet that need, a known lens apparatus has a lens holder which holds a lens and allows an adjustment of the optical axis position of the lens by selecting the position of rotation in putting the lens into a barrel body, and an inclination adjustment mechanism which adjusts the inclination in putting the lens holder into the barrel body to adjust the inclination of the lens with respect to the optical axis. The lens apparatus is provided with a holder carrying member which holds the lens holder rotatable and integrally inclinable, and the inclination adjustment mechanism is coupled to the holder carrying member in the outer diameter direction of the lens holder, thereby achieving the optical adjustment (see Japanese Patent Application Laid-Open No. H11(1999)-212135).
Another known lens apparatus has a lens frame which holds a lens and a holding member which holds the lens frame. The holding member has an adjustment shape portion on which the lens frame abuts in the optical axis direction to make a decentering adjustment of the lens frame to the holding member in the direction perpendicular to the optical axis and a gradual position adjustment in the optical axis direction (see Japanese Patent Application Laid-Open No. 2002-350702).
In the inclination adjustment mechanism proposed in Japanese Patent Application Laid-Open No. H11(1999)-212135, however, the arrangement of the mechanism involves a number of parts to complicate the structure. Also, since it is necessary to provide the space for placing the inclination adjustment mechanism in the outer diameter direction of the lens holder, the lens apparatus is increased in size in the diameter direction.
In addition, the position of the lens subjected to the inclination adjustment is changed in the optical axis direction to result in a focus shift. This requires the action of achieving focus again in order to check whether favorable optical performance is realized after the inclination adjustment, presenting a problem that the inclination adjustment is difficult to perform while the optical performance is checked.
On the other hand, Japanese Patent Application Laid-Open No. 2002-350702 enables the decentering adjustment of the lens in the direction perpendicular to the optical axis and the gradual position adjustment in the optical axis direction. However, the width (space) for allowing the decentering adjustment (movement) of the lens is needed in the direction perpendicular to the optical axis, which causes a problem that the size of the lens apparatus is increased in the diameter direction.